Portable base



FIG. 1 is a perspective view of a portable base, incorporating the new design.

FIG. 2 is a top plan of the portable base of FIG. 1.

FIG. 3 is a bottom plan of the portable base of FIG. 1.

FIG. 4 is a front elevation of the portable base of FIG. 1.

FIG. 5 is a rear elevation of the portable base of FIG. 1.

FIG. 6 is a left side elevation the portable base of FIG. 1; and,

FIG. 7 is a right side elevation the portable base of FIG. 1. 

The ornamental design for a portable base, as shown and described. 